Patent attributes
Examples of an apparatus are disclosed. In some example, an apparatus includes a photodiode configured to generate a charge in response to incident light; a measurement capacitor to store at least a part of the charge to generate a voltage; and an analog-to-digital converter (ADC) circuit configured to: in a first measurement period, compare the voltage at the measurement capacitor against a static threshold voltage to generate a first output; in a second measurement period, compare the voltage against a varying threshold voltage to generate a second output, wherein the varying threshold voltage varies with time according to a pre-determined pattern; and generate a final output representing an intensity of the incident light based on either the first output or the second output.